This node provides the ability to rotate a vector around a center point using either Axis Angle , Single Axis or Euler methods.
This node/diff has gone through a few iterations after the Mapping node was updated in D5541. This is why it has changed since the first diff.
This provides ability to rotate a vector around an origin point and also provide access to the XYZ values via sockets.
Together with D3786 Vector Multipy, this provides sockets and an alternative to the mapping node.
Like the mapping node it uses XYZ order and this could be expanded in future to support other rotation modes.